我正在使用具有MVP架构的分页库。数据源是在交互器中创建的,我正尝试使Fragment中的数据源无效,如下所示。
MyFragment
class MyFragment : BaseFragment<MyFragment>(), MyView {
@Inject
lateinit var mPresenter: ActivePrescriptionPresenter<ActivePrescriptionView>
private var isRefreshRequest = false // Used to handle the visibility of toast message and Swipe to Refresh layout when Swipe to refresh is used
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?): View? {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_active_prescription, container, false)
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
initDagger()
mPresenter.setView(this)
initializeActivePrescriptionList(pId)
// Swipe to refresh
srlActivePrescription.setOnRefreshListener {
isRefreshRequest = true
context?.toast("Refreshing")
mPresenter.getActivePrescriptionLiveData().value?.dataSource?.invalidate()
}
}
private fun initializeActivePrescriptionList(patientId: Int) {
mPresenter.getActivePrescriptionLiveData().observe(this, Observer<PagedList<PrescriptionResponse.Data.Result>> { pagedList ->
activePrescriptionAdapter.submitList(pagedList)
// Show toast message if the swipe to refresh was used
if (isRefreshRequest) {
srlActivePrescription.isRefreshing = false
context?.toast(getString(R.string.text_refreshed))
isRefreshRequest = false
}
})
mPresenter.getNetworkState().observe(this, Observer<NetworkState> { networkState ->
activePrescriptionAdapter.setNetworkState(networkState)
})
}
}
MyPresenterImpl
class MyPresenterImpl @Inject constructor(var mInteractor: myInteractor) : MyPresenter<MyView> {
var mView: WeakReference<MyView>? = null
override fun setView(view: MyView?) {
mView = WeakReference<MyView>(view)
}
override fun getNetworkState(): LiveData<NetworkState> {
return mInteractor.getNetworkState()
}
override fun getActivePrescriptionLiveData(): LiveData<PagedList<PrescriptionResponse.Data.Result>> {
return mInteractor.getActivePrescriptionLiveData()
}
}
MyInteractorImpl
class MyInteractorImpl(val activePrescriptionService: ActivePrescriptionService,
val networkUtils: NetworkUtils<PrescriptionResponse.Data>,
val networkExecutor: Executor,
val pagingConfig: PagedList.Config)
: MyInteractor {
private var activePrescriptionLiveData: LiveData<PagedList<PrescriptionResponse.Data.Result>>
private var networkStateLiveData: LiveData<NetworkState>
companion object {
lateinit var activePrescriptionDataSource: ActivePrescriptionDataSource
}
init {
activePrescriptionDataSource = ActivePrescriptionDataSource(activePrescriptionService, networkUtils, networkExecutor)
val dataSourceFactory = object : DataSource.Factory<Int, PrescriptionResponse.Data.Result>() {
override fun create(): DataSource<Int, PrescriptionResponse.Data.Result> {
return activePrescriptionDataSource
}
}
val pagedListBuilder = LivePagedListBuilder<Int, PrescriptionResponse.Data.Result>(dataSourceFactory, pagingConfig)
activePrescriptionLiveData = pagedListBuilder.build()
networkStateLiveData = activePrescriptionDataSource.getNetworkStateLiveData()
}
override fun getNetworkState(): LiveData<NetworkState> {
return networkStateLiveData
}
override fun getActivePrescriptionLiveData(): LiveData<PagedList<PrescriptionResponse.Data.Result>> {
return activePrescriptionLiveData
}
}
但是问题是,当数据源无效时,什么也不会发生。我需要重新获取刷卡中的列表才能刷新。任何帮助将不胜感激。
P.S。我找不到将Paging库与MVP一起使用的任何示例,因此我自己实现了它。告诉我我在这里做错了什么。
答案 0 :(得分:0)
您必须始终在工厂DataSource
方法内创建create
的新实例:
val dataSourceFactory = object : DataSource.Factory<Int, PrescriptionResponse.Data.Result>() {
override fun create(): DataSource<Int, PrescriptionResponse.Data.Result> {
return ActivePrescriptionDataSource(activePrescriptionService, networkUtils, networkExecutor)
}
一旦DataSource
失效,它将失效-您将无法再使用它。这就是为什么您必须在create()